Where is the Voltage Regulator Located on an Alternator?

Reviewed by

Richard McCuistian, ASE Certified Master Automobile Technician

Technical Reviewer at CarParts.com

Written by CarParts.com Research Team - Updated on November 10th, 2023

Reading Time: 2 minutes
Summary
  • The voltage regulator is responsible for regulating voltage in an electrical circuit.
  • You can find the voltage regulator close to the alternator of your vehicle, usually mounted to its side or, in some cases, inside the alternator itself.
  • To access the voltage regulator, all you need to do is park your vehicle, disconnect the car battery, and check the engine compartment. You should be able to find the voltage regulator near the battery itself.

Q: Where is the Voltage Regulator Typically Located?

A: Older voltage regulators were a unit mounted on the car body. GM moved their voltage regulator into the alternator body in the mid 1970s. Ford moved their voltage regulator into the alternator in the early 1980s. Chrysler moved their voltage regulator into the engine controller in the mid-1980s on some of their platforms.

Since about 2000, most platforms have the voltage regulation built into the PCM, so you might or might not have a voltage regulator on your vehicle. Bear in mind that the exact location of the voltage regulator will vary from vehicle to vehicle. If you’re struggling to find your voltage regulator, your best bet would be to consult your vehicle owner’s manual for the exact location.

The voltage regulator is the part of the charging system responsible for regulating the current in the alternator field (the spinning rotor driven by the pulley). It keeps track of system voltage and regulates the alternator field current to maintain a target voltage of about 14.5 volts.

Various types of voltage regulators for different makes and models | Image Source: Richard McCuistia

Tips on How to Access the Voltage Regulator

To access the voltage regulator, all you need to do is park your vehicle, disconnect the car battery, and check the engine compartment. It’s helpful to look up the voltage regulator for your vehicle on CarParts.com so you can determine what it looks like.

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: Some voltage regulators are easy to change, others, not so much, so make sure you don’t get in over your head to begin with. Also, make sure you know the voltage regulator is the problem before you even start. Something as simple as an open wire between the regulator and the battery light in the cluster can cause the regulator not to “turn on.” There are many other possibilities as well.

Don’t forget to disconnect the car battery before replacing the voltage regulator. Reconnect it after the job is done. Test your vehicle’s electrical system with a multimeter to confirm that your new voltage regulator is working as intended.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.